Surveillance studies in the U.S. have shown an increase in the number of hospitalizations for skin and soft tissue infections (SSTIs) by 29% from 2000 to 2004.1 Moreover, recent studies on the inpatient management of SSTIs have shown significant deviation from recommended therapy, with the majority of patients receiving excessively long treatment courses or unnecessarily broad antimicrobial coverage.2,3
With the ever-increasing threat of antibiotic resistance and rising rates of Clostridium difficile colitis, this update provides clinicians with a set of recommendations to apply antibiotic stewardship while effectively managing SSTIs.4
In June 2014, the Infectious Diseases Society of America (IDSA) published an update to its 2005 guidelines for the treatment of SSTIs.5 For purulent SSTIs (cutaneous abscesses, furuncles, carbuncles, and inflamed epidermoid cysts), incision and drainage is primary therapy. The use of systemic antimicrobial therapy is unnecessary for mild cases, even those caused by methicillin-resistant Staphylococcus aureus (MRSA). The use of empiric adjunctive antibiotics should be reserved for those with impaired host defenses or signs of systemic inflammatory response syndrome (SIRS). The recommended antibiotics in such patients have anti-MRSA activity and include trimethoprim-sulfamethoxazole or doxycycline for moderate infections and vancomycin, daptomycin, linezolid, telavancin, or ceftaroline for severe infections. Antibiotics should subsequently be adjusted based on susceptibilities of the organism cultured from purulent drainage.
Nonpurulent cellulitis without SIRS may be treated on an outpatient basis with an oral antibiotic targeted against streptococci, including penicillin VK, cephalosporins, dicloxacillin, or clindamycin. Cellulitis with SIRS may be treated with an intravenous antibiotic with methicillin-susceptible Staphylococcus aureus (MSSA) activity, including penicillin, ceftriaxone, cefazolin, or clindamycin.
The use of antibiotics with MRSA activity should be reserved for those at highest risk, such as patients with impaired immunity or signs of a deep space infection. Cultures of blood, cutaneous biopsies, or swabs are not routinely recommended; however, prompt surgical consultation is recommended for patients suspected of having a necrotizing infection or gangrene.
The recommended duration of antimicrobial therapy for uncomplicated cellulitis is five days, and therapy should only be extended in those who have not shown clinical improvement. Elevation of the affected area and the use of systemic corticosteroids in nondiabetic adults may lead to a more rapid resolution of cellulitis, although the clinician must ensure that a deeper space infection is not present prior to initiating steroids.
Preventing the recurrence of cellulitis is an integral part of routine patient care and includes the treatment of interdigital toe space fissuring, scaling, and maceration, which may act as a reservoir for streptococci. Likewise, treatment of predisposing conditions such as eczema, venous insufficiency, and lymphedema may reduce the recurrence of infection. In patients who have three to four episodes of cellulitis despite attempts to treat or control predisposing risk factors, the use of prophylactic antibiotics with erythromycin or penicillin may be considered.
For patients with an SSTI during the first episode of febrile neutropenia, hospitalization and empiric therapy with vancomycin and an antipseudomonal beta-lactam are recommended. Antibiotics should subsequently be adjusted based on the antimicrobial susceptibilities of isolated organisms.
For patients with SSTIs in the presence of persistent or recurrent febrile neutropenia, empirically adding antifungal therapy is recommended. Such patients should be aggressively evaluated with blood cultures and biopsy with tissue culture of the skin lesions. The recommended duration of therapy is seven to 14 days for most bacterial SSTIs in the immunocompromised patient.